Dataset Information

Optimal respiratory-gated [¹⁸F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

ABSTRACT:

Purpose

Metabolic parameters are increasingly being used to characterize tumors. Motion artifacts due to patient respiration introduce uncertainties in quantification of metabolic parameters during positron emission tomography (PET) image acquisition. The present study investigates the impact of amplitude-based optimal respiratory gating (ORG) on quantification of PET-derived image features in patients with pancreatic ductal adenocarcinoma (PDAC), in correlation with overall survival (OS).

Methods

Sixty-nine patients with histologically proven primary PDAC underwent 2'-deoxy-2'-[¹⁸F]fluoroglucose ([¹⁸F]FDG) PET/CT imaging during diagnostic work-up. Standard image acquisition and reconstruction was performed in accordance with the EANM guidelines and ORG images were reconstructed with a duty cycle of 35%. PET-derived image features, including standard parameters, first- and second-order texture features, were calculated from the standard and corresponding ORG images, and correlation with OS was assessed.

Results

ORG significantly impacts the quantification of nearly all features; values of single-voxel parameters (e.g., SUV_max) showed a wider range, volume-based parameters (e.g., SUV_mean) were reduced, and texture features were significantly changed. After correction for motion artifacts using ORG, some features that describe intra-tumoral heterogeneity were more strongly correlated to OS.

Conclusions

Correction for respiratory motion artifacts using ORG impacts the quantification of metabolic parameters in PDAC lesions. The correlation of metabolic parameters with OS was significantly affected, in particular parameters that describe intra-tumor heterogeneity. Therefore, interpretation of single-voxel or average metabolic parameters in relation to clinical outcome should be done cautiously. Furthermore, ORG is a valuable tool to improve quantification of intra-tumoral heterogeneity in PDAC.

SUBMITTER: Smeets EMM

PROVIDER: S-EPMC6419652 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

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Publications

Optimal respiratory-gated [<sup>18</sup>F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

Smeets Esther M M EMM Withaar Dominique S DS Grootjans Willem W Hermans John J JJ van Laarhoven Kees K de Geus-Oei Lioe-Fee LF Gotthardt Martin M Aarntzen Erik H J G EHJG

EJNMMI research 20190313 1

<h4>Purpose</h4>Metabolic parameters are increasingly being used to characterize tumors. Motion artifacts due to patient respiration introduce uncertainties in quantification of metabolic parameters during positron emission tomography (PET) image acquisition. The present study investigates the impact of amplitude-based optimal respiratory gating (ORG) on quantification of PET-derived image features in patients with pancreatic ductal adenocarcinoma (PDAC), in correlation with overall survival (OS ...[more]

PMID: 30868318

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Project description:Knowledge of the within-subject variability of 18F-FDG PET/MRI measurements is necessary for proper interpretation of quantitative PET or MRI metrics in the context of therapeutic efficacy assessments with integrated PET/MRI scanners. The goal of this study was to determine the test-retest repeatability of these metrics on PET/MRI, with comparison to similar metrics acquired by PET/CT. Methods: This prospective study enrolled subjects with pathology-proven pelvic malignancies. Baseline imaging consisted of PET/CT immediately followed by PET/MRI, using a single 370-MBq 18F-FDG dose. Repeat imaging was performed within 7 d using an identical imaging protocol, with no oncologic therapy between sessions. PET imaging on both scanners consisted of a list-mode acquisition at a single pelvic station. The MRI consisted of 2-point Dixon imaging for attenuation correction, standard sequences for anatomic correlation, and diffusion-weighted imaging. PET data were statically reconstructed using various frame durations and minimizing uptake time differences between sessions. SUV metrics were extracted for both PET/CT and PET/MRI in each imaging session. Apparent diffusion coefficient (ADC) metrics were extracted for both PET/MRI sessions. Results: The study cohort consisted of 14 subjects (13 female, 1 male) with various pelvic cancers (11 cervical, 2 rectal, 1 endometrial). For SUVmax, the within-subject coefficient of variation (wCV) appeared higher for PET/CT (8.5%-12.8%) than PET/MRI (6.6%-8.7%) across all PET reconstructions, though with no significant repeatability differences (all P values ≥ 0.08) between modalities. For lean body mass-adjusted SUVpeak, the wCVs appeared similar for PET/CT (9.9%-11.5%) and PET/MRI (9.2%-11.3%) across all PET reconstructions, again with no significant repeatability differences (all P values ≥ 0.14) between modalities. For PET/MRI, the wCV for ADCmedian of 3.5% appeared lower than the wCVs for SUVmax (6.6%-8.7%) and SULpeak (9.2%-11.3%), though without significant repeatability differences (all P values ≥ 0.23). Conclusion: For solid tumors of the pelvis, the repeatability of the evaluated SUV and ADC metrics on 18F-FDG PET/MRI is both acceptably high and similar to previously published values for 18F-FDG PET/CT and MRI, supporting the use of 18F-FDG PET/MRI for quantitative oncologic treatment response assessments.

Project description:BackgroundMagnetic resonance imaging (MRI) plays an important role in the diagnosis of leptomeningeal metastases (LM); however, some sub-centimeter lesions may be missed. Positron emission tomography/computed tomography (PET/CT) has a high sensitivity and may play a synergistic role with MRI in diagnosing spinal LM (SLM). We aimed to retrospectively evaluate the detection of SLM with 18F-fluorodeoxyglucose PET/CT (18F-FDG PET/CT) compared to that of whole spinal cord MRI in a single center.MethodsPatients with SLM who had undergone 18F-FDG PET/CT and MRI were enrolled. 18F-FDG PET/CT imaging findings were independently reviewed by 2 nuclear medicine physicians. 18F-FDG PET/CT findings of SLMs were described. A consistency test was conducted to assess the patient-based diagnostic results obtained by the 2 physicians. Patient-based sensitivity, accuracy, and specificity in diagnosing SLM between 18F-FDG PET/CT and MRI of the whole spinal cord were compared using the chi-square or Fisher's exact test. A P value of <0.05 was considered statistically significant. The receiver operating characteristic (ROC) curve was obtained to assess the diagnostic performance of maximum standardized uptake value (SUVmax) to diagnose SLM.ResultsA total of 16 patients with SLM were included in this study from October 2010 to April 2022. The primary tumor involved the lungs, liver, ovaries, prostate, esophagus, and unknown primary site. The mean age of patients, including 13 males and 3 females, was 57.8±11.2 (range, 34-73) years. Of 16 patients with SLM, 10 had nodular diseases, 2 had linear diseases, and 4 had mixed diseases. The kappa value of the consistency test of the 2 radiologists' diagnostic results was 0.765. The patient-based sensitivity, specificity, and accuracy of 18F-FDG PET/CT in diagnosing SLM were 87.5%, 89.2%, and 88.7%, respectively and those of whole spinal cord MRI were 75.0%, 100.0%, and 92.5%, respectively. There were no significant differences in sensitivity, specificity, and accuracy between the 2 methods, with P values of 0.654, 0.115, and 0.506, respectively. However, more nodular diseases were observed on PET/CT. The area under the ROC curve (AUC) for the prediction of SLM by SUVmax was 0.907 [95% confidence interval (CI): 0.831-0.983]. When SUVmax ≥2.45, the Youden index was the largest, and the sensitivity and specificity were 89.3% and 75.7%, respectively.Conclusions18F-FDG PET/CT is a good choice of imaging modality for assessing SLM. In the diagnosis of SLMs, PET/CT and enhanced MRI can play a better synergistic role.

Project description:PurposeThis study aimed to assess the diagnostic performance of [18F]FAPI-42 PET/CT and compare it with that of 2-[18F]FDG PET/CT in patients with differentiated thyroid cancer (DTC) with biochemical elevations in Tg or anti-Tg antibodies.MethodsA total of 42 patients with DTC with biochemical elevations in Tg or anti-Tg antibodies underwent [18F]FAPI-42 PET/CT as part of this study; of which, 11 additionally underwent 2-[18F]FDG PET/CT within 7 days. Images were semi-quantitatively and visually interpreted, and the quantity, location, and uptake values of lesions were noted. The diagnostic capacity of [18F]FAPI-42 PET/CT and biomarkers affecting the uptake of [18F]FAPI-42 were evaluated. In addition, the diagnostic performance and uptake of [18F]FAPI-42 and 2-[18F]FDG were compared, and the correlation between lesion diameter and quantitative parameters was investigated.ResultsA total of 161 lesions were detected in 27 (64%) patients on [18F]FAPI-42 PET/CT. FAPI-positive local recurrence showed the highest uptake intensity, followed by lymphatic, other site-associated (bone and pleura), and pulmonary lesions (mean SUVmax, 4.7 versus 3.7 versus 3.0 versus 2.2, respectively; P < 0.0001). The levels of TSH, Tg, and Tg-Ab did not affect the uptake value of lesions (median SUVmax: 2.4 versus 3.2, P = 0.56; 2.9 versus 2.4, P = 0.0935; 2.8 versus 2.6, P = 0.0525, respectively). A total of 90 positive lesions were detected in 7 patients using both modalities. All positive lesions showed statistically higher uptake of 2-[18F]FDG than that of [18F]FAPI-42 (SUVmax, 2.6 versus 2.1; P = 0.026). However, the SUVmax of [18F]FAPI-42 was higher than that of 2-[18F]FDG in local recurrences and lymphatic lesions (SUVmax, 4.2 versus 2.9 and 3.9 versus 3.4, respectively; P > 0.05).Conclusion[18F]FAPI-42 can be used for detecting lesions and reflecting FAP expression during local recurrence and metastasis in patients with DTC with biochemical elevations in Tg or anti-Tg antibodies. The diagnostic performance of [18F]FAPI-42 PET/CT is comparable with that of 2-[18F]FDG PET/CT in such patients.

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Dataset Information

Optimal respiratory-gated [¹⁸F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

Purpose

Methods

Results

Conclusions

Publications

Optimal respiratory-gated [<sup>18</sup>F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Dataset Information

Optimal respiratory-gated [18F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

Purpose

Methods

Results

Conclusions

Publications

Optimal respiratory-gated [<sup>18</sup>F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Optimal respiratory-gated [¹⁸F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma.